To meet the demand for wireless data traffic having increased since deployment of 4th generation (4G) communication systems, efforts have been made to develop an improved 5th generation (5G) or pre-5G communication system. The 5G or pre-5G communication system is also called a ‘beyond 4G network’ or a ‘post long term evolution (LTE) system’. The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beamforming, and large scale antenna techniques are discussed with respect to 5G communication systems. In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, coordinated multi-points (CoMP), reception-end interference cancellation and the like. In the 5G system, hybrid frequency shift keying (FSK) and Feher's quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
The Internet, which is a human centered connectivity network where humans generate and consume information, is now evolving to the Internet of things (IoT) where distributed entities, such as things, exchange and process information without human intervention. The Internet of everything (IoE), which is a combination of the IoT technology and the big data processing technology through connection with a cloud server, has emerged. As technology elements, such as “sensing technology”, “wired/wireless communication and network infrastructure”, “service interface technology”, and “security technology” have been demanded for IoT implementation, a sensor network, a machine-to-machine (M2M) communication, machine type communication (MTC), and so forth have been recently researched. Such an IoT environment may provide intelligent Internet technology services that create a new value to human life by collecting and analyzing data generated among connected things. IoT may be applied to a variety of fields including smart home, smart building, smart city, smart car or connected cars, smart grid, health care, smart appliances and advanced medical services through convergence and combination between existing information technology (IT) and various industrial applications.
In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as a sensor network, MTC, and M2M communication may be implemented by beamforming, MIMO, and array antennas. Application of a cloud RAN as the above-described big data processing technology may also be considered to be as an example of convergence between the 5G technology and the IoT technology.
Mobile communication systems were developed to provide the subscribers with voice communication services on the move. With the rapid advance of technologies, the mobile communication systems have evolved to support high speed data communication services beyond the early voice-oriented services. However, the limited resource and user requirements for higher speed services in the current mobile communication system spur the evolution to more advanced mobile communication systems.
The LTE-advanced (LTE-A) of the 3rd generation partnership project (3GPP) is a technology for realizing high-speed packet-based communications at the data rate of up to 100 Mbps. In the LTE-A, the number of cells serving a user equipment (UE) increases while feedback for all of the serving cells are transmitted through a primary cell (PCell). Also, in LTE-A, all of the cells serving one UE operate in the same duplex mode. Accordingly, all of the cells may operate in the frequency division duplex (FDD) mode or time division duplex (TDD) mode. Among them, the TDD mode can be categorized into one of the static TDD mode in which the uplink (UL)-downlink (DL) configuration is maintained and the dynamic TDD mode in which the UL-DL configuration varies by means of the system information, higher layer signal, or DL common control channel.
In the case where a cell under the control of the evolved node B (eNB) operates in the FDD mode and one frequency band is added, it is easy to adopt the TDD mode to the added frequency. This is because the FDD mode requires two frequency bands for DL and UL respectively.
In the case where there are cells operating in different duplex modes due to the addition of a restrictive frequency as aforementioned or other reasons, a method for transmitting the control channel corresponding to the data transmitted through multiple cells is required. In the case where the feedback carrying the UL control channels associated with multiple cells in correspondence to the DL data are transmitted through only the PCell, there is a need of a technique for the UE to transmit the feedback for the cells having different frame structures through the PCell. Also, there is a need of a technique for the eNB to schedule the UL transmission of the UE in association with the DL control channel corresponding to the UL data and to transmit the DL control channel corresponding to the UL data.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.